The BRZ / FR-S / GT 86 transmissions and driveline: what we know so far

[WingsofWar]

Originally Posted by mact

Hopefully there will be some company that will offer strengthened gear sets.

sure but at a incredibly high price that makes it not worth a damn.

Id cryo treat my factory gears before i look into getting a brand new stronger aftermarket one that will put me $10k+ in the hole.

and before even that..id look into retrofitting another transmission into the car. Bellhousing adapters might make it more worth while.

[old greg]

Originally Posted by mact

Hopefully there will be some company that will offer strengthened gear sets.

Pfitzner Performance Gearbox is already making gearsets for the AZ6.

But like WoW said, if I was making enough torque to need gears like that, I'd rather save myself ~$6000 and run something like a TKO-600 with a spun steel bellhousing and custom length driveshaft instead.

[Dimman]

Originally Posted by old greg

Pfitzner Performance Gearbox is already making gearsets for the AZ6.

But like WoW said, if I was making enough torque to need gears like that, I'd rather save myself ~$6000 and run something like a TKO-600 with a spun steel bellhousing and custom length driveshaft instead.

Hmm, I guess a Honda CAN do that.

[OrbitalEllipses]

Originally Posted by Dimman

Hmm, I guess a Honda CAN do that.

[jruhi4]

Thank you, all, for the kind words and warm welcome.

Originally Posted by brzmaybe

First, is there any way for you to estimate the weight difference between the manual and automatic transmissions?

I picked up the following curb weight numbers for the different JDM Toyota 86 models from their official website:

RC Manual: 2601 lbs (1180 kg)
G Manual: 2662 lbs (1210 kg)
G Automatic: 2706 lbs (1230 kg)
GT Manual: 2706 lbs (1230 kg)
GT Automatic: 2750 lbs (1250 kg)
GT Limited Manual: 2706 lbs (1230 kg)
GT Limited Automatic: 2750 lbs (1250 kg)

Thus, the automatics are 44 lbs (20 kg) heavier than the manuals.

Originally Posted by brzmaybe

Second, do you have any comments on a couple of "first drive" review articles suggesting that the automatic might, all things being considered, be just a little bit faster around the track?

Indeed, I've seen those, and wonder if differences in the individual manual vs automatic gear ratios might account for some of this.

One thing I will say, though, is how Toyota/Lexus have applied their philosophy of kaizen, or continuous improvement, to the A760E high torque capacity 6-speed automatic. This is what is in my current daily driver, a 2011 Lexus IS 350 F Sport. Last November, though, I was invited to the long lead press preview for the 4th-generation Lexus GS 350 that is just arriving in dealerships (and shares the same transmission). The tweaks mentioned in my article (earlier torque converter lockup, faster upshift and downshift times and rev-matching throttle blips accompanying downshifts) make a notable and impressive difference versus my older iteration of the same transmission. And, from what I've read, the lighter A960E automatic from the IS 250 RWD has also received these tweaks as it appears on the Toyobaru triplets.

Personally, I think it's sacrilegious to get an FR-S or BRZ with an automatic transmission, but it seems that those that do make this choice should be quite happy and will have among the best and most responsive torque-converter automatics out there.

[jruhi4]

By the way, thanks for moving the thread. You're right, it's a much better fit in this forum. I didn't really see it when I started the thread.

[rL-gT]

Was just about to hot link this from my.IS LOL.

[Geezy]

I had been seriously considering getting the AT version over the manual, but the gear ratios on the auto have me confused. Does anybody know the reasoning for why fifth and sixth gear are overdrive?

Here are the ratios for reference:

Manual

1. 3.626
2. 2.188
3. 1.541
4. 1.213
5. 1.000
6. 0.767

Reverse: 3.168
Final: 4.100

Auto

1. 3.538
2. 2.060
3. 1.404
4. 1.000
5. 0.713
6. 0.582

Reverse: 3.168
Final: 4.100

[serialk11r]

Well, jruhi4 speculated that the transmission is pulled from some other car in the Toyota lineup...they probably didn't bother modifying it very much. And fuel economy.

[Dimman]

^ Fuel economy at cruise/highway.

[jruhi4]

Originally Posted by Geezy

Does anybody know the reasoning for why fifth and sixth gear are overdrive?

That's typical of all Toyota/Lexus 6-speed automatics, be they FWD transaxles or RWD transmissions. And the 8-speed automatics (IS F, LS) also have 6th speed direct and overdrives on 7th and 8th.

I'm pretty sure the main reason is for better EPA cycle highway fuel economy numbers, with quieter, more relaxed freeway cruising as a side bonus.

[serialk11r]

I think the reason you want 2 overdrives instead of 1 though is the last gear would make the engine run too slow at say 30mph or so, so they have a slightly shorter overdrive so you can roll along barely above idle at say 25mph or something. Good for city fuel economy.